Carburetor



Nov. 26, 1935. M. E; CHANDLER 2 2,022,027

CARBURETOR Filed May 7, m1

F INVENTOR.

2 ML row 5 CHANDLER By M 7 M A TTORNE Y.

Patented Nov. 26, 1935 UNITED, STATES PATENT OFFICE cnanvan'roa Milton E. Chandler, South Bend, Ind., assignor to Bendix Stromberg Carburetor Company, South Bend,'lnd., a corporation of Illinois Application May 7, 1931, Serial No. 535,713

11 Claims.

This invention relates to carburetors and more particularly to a thermostatic control of a fuel feeding device for a carburetor such as an acceleration pump. v

An object of the invention is to provide a carburetor in which the quantity of fuel discharged by the acceleration pump is decreased with an.

The fuel charge delivered by the pump is usually -constant for each pump stroke and no compensation is made for temperature although it is known by, those skilled in the art that the need for additional fuel varies inversely with the temperature.

A feature of the present invention is to provide the discharge conduits of 'the acceleration pump with a thermostat .which will reduce the charge as the temperature rises.

Other objects and features 'of the invention willbe apparent from the following description in connection with which I have illustrated theinvention in the accompanying drawing in which:

Figure 1 is a vertical cross section of a car- -buretor embodying the invention; and v Figure 2 is an enlarged fragmentary view in cross section 01: the control valve.

- In the drawing, I0 is a'carburetor' having a throttle valve l2 pivotally mounted on a shaft It to which is secured a cam it which contacts with lever l8 and depresses cylinder 20 to force fuel from the float chamber 22 through the conduit 24 to the discharge orifice 26 thatopens into the mixing chamber 28. The acceleration pump comprises a reciprocating cylinder 20; piston 30, which is held in its upper position by spring 32 and slidably mounted -on the guide 33, all of the acceleration pump is constant under ordinary conditions and as it is desirable to reduce the charge when the external temperature is increased,I have provided a cross passage 46 which communicates with conduit 24 and in which is mounted a needle valve 38 having a head at its '5 outer end to which is attached a U-shaped thermostat lllwhich is riveted or otherwise secured to a fixed portion of the carburetor such as threaded plug 42. Thermostat 40, which is preferably formed of two metals having different 00- 10 efficients of expansion, is arranged in a'manner to insert valve 38 and cut offcommunication between passages 46 and 24 when the temperature is increased.

In operation, it will. be seen that valve 38 is are 15 ranged to directly control the passage leading to orifice 26. The thermostat 40 is so arranged that an increase in temperature forces valve 38 toward the left, as viewed in the drawing, and closes passage 46 which leads to the discharge orifice 26.

While I have illustrated and described an embodiment of the invention, it is to be understood that this showing and description are illustrative only, and that I do not regard the invention as limited to the form shown and described, or other- 25 wise, except by the terms of the following claims.

I claim:

1. A carburetor comprising a mixing chamber, an acceleration pump having its outlet terminating in the mixing chamber, a, valve in said outlet, 39

and a thermostat for controlling the valve.

2. A carburetor comprising a mixing chamber, an acceleration pump having its outlet terminating in the mixing chamber, a valve in said outlet, and a U-shaped thermostat for controlling the valve having one'end secured to the carburetor and the other end secured to the valve.

3. A carburetor-comprising a fuel reservoir, a main fuel passage, an auxiliary fuel passage, a pump supplying fuel thereto, a valve for chang ing the eifective cross sectional area of the auxiliary fuel passage, and a thermostat arranged to open said valve with a decrease in temperature. 1

4. In a carburetor having-a mixing chamber "5 and a throttle, an acceleration pump having a fuel outlet terminating in said chamber, athermostatic valve controlling the effective size of said outlet, the stroke of said pump being always proportional to the movement of said throttle 50 regardless of the position of said valve.

' 5. In a carburetor having a mixing chamber and-athrottleyan acceleration pump comprising a reciprocating cylinder, afuel passageway from said cyliider terminating in said chamber, and B5 a thermostatic valve controlling the effective size of said passageway. a

6. In a carburetor having a mixing chamber and a throttle, an acceleration pump comprising a reciprocating cylinder, 9. fuel passageway from said cylinder terminating in said chamber, and athermostatic valve controlling the eifective size of said passageway, the stroke of said cylinder being always proportional to the movement .of said throttle regardless of the position of'said valve.

7. In a carburetor having a mixing chamber with a main fuel jet therein, an acceleration pump operable in accordance with throttle position and having a fuel outlet separate from said main jet and terminating in the zone .of the greatest air velocity through said chamber, and a thermostatic valve controlling the fuel issuing from said outlet by varying the effective size of the outlet.

8. In a carburetor having a main air passageway with a main fuel Jet therein, a throttle actuated acceleration pump comprising a reciprocating cylinder and piston, having a fuel outlet separate from said main jet and terminating in the zone of the highest velocity of air through said passageway, and a thermostatic valve controlling the quantity of fuel issuing from said outlet by changing the effective size of the fuel outlet.

9. In a carburetor, a main induction passage, a throttle valve, an acceleration pump having a reciprocating cylinder, a fixed stem and a spring pressed piston membena fuel passage from the acceleration pump to the induction passage, valve means controlling the fuel passage, thermostatic means for actuating the valve means to vary the effective size of the fuel passage, and throttle actuated means for reciprocating the cylinder through a stroke always proportional to the movement of the throttle valve regardless of the position of the thermostatic means.

10. A carburetor having a main induction passage, a throttle valve, a throttle actuated acceleration pump comprising a cylinder and a reciprocating piston, a fuel passage from the acceleration pump to the induction passage, a. valve means controlling the fuel passage, thermostatic means for actuating the valve meansand controlling the effective size of said fuel passage, the stroke of said piston being always proportional to the movement of the throttle valve regardless of the position of the themiostatic means.

11. In a carburetor, a mixing chamber, a venturi, a main fuel jet positioned to discharge at the most restricted section of the venturi, a throttle valve, an acceleration pump including a throttle actuated reciprocating cylinder having a 25 stroke always proportional to the movement of the throttle, a fuel outlet from the acceleration pump separate from the main fuel jet and terminating in the most restricted section of the venturi, and a thermostatically controlled valve 30 operable to vary the effective size of the fuel outlet from the acceleration pump.

. MILTON E. CHANDLER. 

